# NTSB WPR13CA092: Heinz Rans S-4 Coyote, N571K, Lake Pleasant, AZ, January 11, 2013

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Data collection · Final report
- Date: January 10, 2013, 17:04 local (Jan 11, 2013, 00:04 UTC)
- Place: Lake Pleasant, AZ
- Coordinates: 33.923889, -112.234443 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=33.9239&lon=-112.2344&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Defining event: [Enroute-cruise: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report April 3, 2013
- Report: Approved by Office Director
- NTSB office: Western Pacific Region
- Parties: Federal Aviation Administration
- NTSB case key (mKey): 86032
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR13CA092
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/86032/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=86032
- Page: https://openairdocs.org/ntsb/WPR13CA092

## Probable cause

A partial loss of engine power during cruise flight for reasons that could not be determined because the airplane was not recovered.

## Findings

NTSB's coded findings; those marked are part of the probable cause.

- [Terrain: water](https://openairdocs.org/ntsb-findings/03021020): Environmental issues › Physical environment · Not specified; cases with it: [Eric P Heinz RANS S-4 COYOTE, 1 case](https://openairdocs.org/ntsb-findings/03021020/cases.md?model=05631QP), [All aircraft, 97 cases](https://openairdocs.org/ntsb-findings/03021020/cases.md)
- [Not determined](https://openairdocs.org/ntsb-findings/05000000): Not determined › Not determined · Unknown/Not determined (probable cause); cases with it: [Eric P Heinz RANS S-4 COYOTE, 1 case](https://openairdocs.org/ntsb-findings/05000000/cases.md?model=05631QP), [All aircraft, 2,247 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md)

## Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event best describes what happened.

- [Enroute-cruise: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Eric P Heinz RANS S-4 COYOTE, 1 case](https://openairdocs.org/ntsb-events/342/sequence.md?model=05631QP), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md)
- [Emergency descent: Ditching](https://openairdocs.org/ntsb-events/441); cases with it: [Eric P Heinz RANS S-4 COYOTE, 1 case](https://openairdocs.org/ntsb-events/441/sequence.md?model=05631QP), [All aircraft, 186 cases](https://openairdocs.org/ntsb-events/441/sequence.md)

## Analysis

The pilot stated that, after about 30 minutes of flight, he advanced the throttle and the engine went to idle power then stopped. He restarted the engine and determined that it would only operate at idle power before it stopped again. He was flying over rocky terrain and determined that the best option was to ditch the airplane in a nearby river. After ditching the airplane in the river, the pilot swam to shore. The airplane sank and will not be recovered.

## Factual narrative

The pilot stated that after about 30 minutes of flight he advanced the throttle and the engine went to idle power, then stopped. He restarted the engine and determined that it would only operate at idle power before it stopped again. He was over rocky terrain and determined that the best option was to ditch the airplane in the river he was flying over. After he ditched the airplane in the river, he swam to shore. The airplane sank and will not been recovered.

## Aircraft

- Registration: [N571K](https://openairdocs.org/deregistered/N571K-2014-02-10), registration cancelled 2014-02-10, S/N 0308336, built 2012 (OpenAirDocs)
- Reported make and model: Heinz Rans S-4 Coyote
- Registry model: [Eric P Heinz RANS S-4 COYOTE](https://openairdocs.org/model/eric-p-heinz-rans-s-4-coyote) (registry code 05631QP) (OpenAirDocs)
- Registry engine: [Rotax 503 series](https://openairdocs.org/engine/rotax-503-series) (registry code 55564, 2 cycle) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 0308336
- Airframe hours: 57
- Engines: Rotax 503 52 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Eric P. Heinz
- Registered owner: Eric P. Heinz
- Airworthiness certificate: Special, Experimental (Special)
- Departed: KP48, Peoria, AZ
- Destination: KP48, Peoria, AZ
- Flight plan: Unknown
- Airport: KP48, Peoria

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 58; injuries: none; student; medical: class 3; seat: center; flight hours: 905 total, 430 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Wind: 110° at 9 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 52 °F, dew point 23 °F
- Altimeter: 29.90 inHg
- Observed at: KDVT, 12 nm away

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 20130110000279A](https://openairdocs.org/incident/20130110000279A), Jan 10, 2013: Eric P Heinz RANS S-4 COYOTE, Peoria, AZ, Substantial damage. After doing a preflight inspection, pilot departed pleasant valley airport at approx 4:30 pm for a short flight to the north end of lake pleasant . The terrain…

## Docket (1 files)

The files NTSB released with the investigation on February 11, 2013, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=86032. 589 KB in all.

- Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 589 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40386301&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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